The lawsuit seeks to halt the sale of the ring in an online auction that ends Friday. It also seeks unspecified damages over broadcast remarks that Lelands' founder, Joshua Evans, made about Brown.

Evans said Wednesday that Brown's claims "are entirely without merit and we intend to vigorously defend against them."

According to the lawsuit, the ring was stolen from Brown's Cleveland home in the late 1960s and the robbery was reported to police.

The lawsuit also accuses Evans of making statements in print and broadcast interviews in recent weeks that implied Brown has diminished mental capacity as a result of taking thousands of hits as a football player. On at least one broadcast, though, Evans could be heard describing Brown as the greatest football player of all time and saying Brown was aware that a family member had sold the ring in the 1990s.

The lawsuit said the ring is priceless to the former Cleveland Browns player. The highest bid was $58,948 Wednesday afternoon.

Evans said Lelands' position is the paperwork over the ownership of the ring is "indisputable" and anyone who bought it would get a 100 percent guarantee.

Brown, who works as a Cleveland Browns special adviser, rushed for 12,312 yards and scored 106 touchdowns in nine seasons before retiring at the peak of his career in 1965. In 1964, he rushed for 1,446 yards and scored seven touchdowns as the Browns won the title, the last for any major Cleveland sports franchise.